[App Service] az webapp up: Add parameter --domain-name-scope to support specifying the scope of uniqueness for the default hostname during resource creation

src/azure-cli/azure/cli/command_modules/appservice/_help.py

@@ -2615,6 +2615,9 @@
   - name: Create a web app and deploy as a static HTML app.
     text: >
         az webapp up --html
+  - name: Create a web app with a specified domain name scope for unique hostname generation
+    text: >
+        az webapp up -n MyUniqueAppName --domain-name-scope TenantReuse
 """
 
 helps['webapp update'] = """

src/azure-cli/azure/cli/command_modules/appservice/_params.py

@@ -972,6 +972,7 @@ def load_arguments(self, _):
                    arg_type=get_three_state_flag())
         c.argument('enable_kudu_warmup', help="If true, kudu will be warmed up before performing deployment for a linux webapp.",
                    arg_type=get_three_state_flag())
+        c.argument('auto_generated_domain_name_label_scope', options_list=['--domain-name-scope'], help="Specify the scope of uniqueness for the default hostname during resource creation.", arg_type=get_enum_type(AutoGeneratedDomainNameLabelScope))
 
     with self.argument_context('webapp ssh') as c:
         c.argument('port', options_list=['--port', '-p'],

src/azure-cli/azure/cli/command_modules/appservice/custom.py

@@ -9082,7 +9082,8 @@ def get_history_triggered_webjob(cmd, resource_group_name, name, webjob_name, sl
 
 def webapp_up(cmd, name=None, resource_group_name=None, plan=None, location=None, sku=None,  # pylint: disable=too-many-statements,too-many-branches
               os_type=None, runtime=None, dryrun=False, logs=False, launch_browser=False, html=False,
-              app_service_environment=None, track_status=True, enable_kudu_warmup=True, basic_auth=""):
+              app_service_environment=None, track_status=True, enable_kudu_warmup=True, basic_auth="",
+              auto_generated_domain_name_label_scope=None):
     if not name:
         name = generate_default_app_name(cmd)
 
@@ -9228,7 +9229,8 @@ def webapp_up(cmd, name=None, resource_group_name=None, plan=None, location=None
     if _create_new_app:
         logger.warning("Creating webapp '%s' ...", name)
         create_webapp(cmd, rg_name, name, plan, runtime_version if not html else None,
-                      using_webapp_up=True, language=language)
+                      using_webapp_up=True, language=language,
+                      auto_generated_domain_name_label_scope=auto_generated_domain_name_label_scope)
         _configure_default_logging(cmd, rg_name, name)
     else:  # for existing app if we might need to update the stack runtime settings
         helper = _StackRuntimeHelper(cmd, linux=_is_linux, windows=not _is_linux)

src/azure-cli/azure/cli/command_modules/appservice/tests/latest/test_webapp_up_commands.py

@@ -8,6 +8,7 @@
 
 import unittest
 import os
+import re
 from pytest import skip
 import requests
 from knack.util import CLIError
@@ -1369,6 +1370,58 @@ def test_webapp_up_track_runtimestatus_runtimefailed(self, resource_group):
         import shutil
         shutil.rmtree(temp_dir)
 
+    @live_only()
+    @AllowLargeResponse(8192)
+    @ResourceGroupPreparer(random_name_length=24, name_prefix='clitest', location=LINUX_ASP_LOCATION_WEBAPP)
+    def test_webapp_up_with_domain_name_scope(self, resource_group):
+        plan = self.create_random_name('up-dnlplan', 24)
+        webapp_name = self.create_random_name('up-dnl-app', 24)
+        zip_file_name = os.path.join(TEST_DIR, 'node-Express-up.zip')
+
+        import zipfile
+        import tempfile
+        temp_dir = tempfile.mkdtemp()
+        zip_ref = zipfile.ZipFile(zip_file_name, 'r')
+        zip_ref.extractall(temp_dir)
+        current_working_dir = os.getcwd()
+
+        up_working_dir = os.path.join(temp_dir, 'myExpressApp')
+        os.chdir(up_working_dir)
+
+        # test dryrun with --domain-name-scope
+        result = self.cmd('webapp up -n {} --dryrun --domain-name-scope TenantReuse'.format(
+            webapp_name)).get_output_in_json()
+        self.assertTrue(result['name'].startswith(webapp_name))
+        self.assertIn("node|", result['runtime_version'].lower())
+        self.assertEqual(result['os'].lower(), 'linux')
+
+        # test the full E2E operation works
+        self.cmd('webapp up -n {} -g {} --plan {} --domain-name-scope TenantReuse'.format(
+            webapp_name, resource_group, plan)).get_output_in_json()
+
+        # Verify app is created with domain name scope
+        result = self.cmd('webapp show -n {} -g {}'.format(webapp_name, resource_group), checks=[
+            JMESPathCheck('name', webapp_name),
+            JMESPathCheck('state', 'Running'),
+            JMESPathCheck('resourceGroup', resource_group),
+            JMESPathCheck('autoGeneratedDomainNameLabelScope', 'TenantReuse')
+        ]).get_output_in_json()
+
+        # Verify the default hostname matches the regional pattern with hash
+        default_hostname = result.get('defaultHostName')
+        pattern = r'^([a-zA-Z0-9\-]+)-([a-z0-9]{16})\.([a-z]+-\d{2})\.azurewebsites\.net$'
+        match = re.match(pattern, default_hostname)
+        self.assertIsNotNone(match, "defaultHostName '{}' does not match expected pattern".format(default_hostname))
+        app_name, hash_part, region = match.groups()
+        self.assertTrue(len(hash_part) == 16 and hash_part.islower(), "Hash is not 16 chars or not lowercase.")
+        self.assertIn('-', region, "Region part does not have '-' separator.")
+        self.assertEqual(app_name, webapp_name, "App name and defaultHostName app name do not match.")
+
+        # cleanup
+        os.chdir(current_working_dir)
+        import shutil
+        shutil.rmtree(temp_dir)
+
 
 if __name__ == '__main__':
     unittest.main()